External capsular hyperintensities on the T2-weighted magnetic resonance imaging (MRI) may be the only magnetic resonance imaging (MRI) findings in a case of Wilson disease, a recently published study in Neurology India found.

The current study was about a 16-year-old boy affected with a rare type of Wilson’s disease with unusual imaging features. The patient was identified with refractory status epilepticus and was experiencing generalized tonic-clonic seizures for the past 16 hours without acquiring consciousness in between the seizures.

Moreover, liver function tests of the patient reported serum bilirubin of 0.5, serum glutamic pyruvic transaminase of 51.6 mg/L, direct bilirubin of 0.1, alkaline phosphatase of 145 mg/dl, and serum glutamic-oxaloacetic transaminase of 46.5 mg/dl. Additionally, the renal function tests of the patient indicated a blood urea nitrogen of 44 mg/dl and serum creatinine of 1.0 mg/dl. 

Read more about Wilson disease therapies

MRI of the patient’s head indicated bilateral T2 and T2 flair external capsular hyperintensities accompanied by restricted diffusion in the previously mentioned areas. Slit-lamp examination indicated no KF ring; however, due to a previous history of jaundice and mildly deranged liver function tests, the patient was examined for serum ceruloplasmin and 24-hour urinary copper levels. The results showed that the ceruloplasmin levels were borderline low (18 mg/dl); however, increased excretion of copper in the urine (139 mcg/24h) was reported. 

Once the WD diagnosis was made, the patient was initiated with zinc acetate, and the d-penicillamine dose steadily increased. This slowly improved the patient’s consciousness, and he was discharged and followed up for 1 year. The patient had 1 episode of the generalized tonic-clonic seizure when he skipped a dose of antiseizure medications. After more than 6 months of treatment, the follow-up MRI, including the diffusion-weighted sequences, was performed, which did not show any abnormalities detected earlier.

The authors concluded that cerebral copper deposition and metabolic encephalopathy in the treated patient appear to be the potential mechanisms of status epilepticus. The research team commented that the serum copper levels, penicillamine challenge test, adenosine triphosphatase 7B gene (ATP7B) gene mutation analysis, and liver biopsy of the patient were not performed at the demonstration, which is a limitation of their study.

“The present case is unique as here there was status epilepticus with atypical MRI findings, which have probably not been reported earlier,” the authors wrote.

“Timely recognition and management of this condition possibly prevented the occurrence of some other serious future complication,” the researchers concluded.

Wilson’s disease is an autosomal recessive disorder caused by mutations in the ATP7B, resulting in copper accumulation in different body tissues, including the brain, kidney, liver, and eye. Neurologic Wilson’s might result in numerous neuropsychiatric symptoms.

Reference

Ruchika T, Madhukar M, Abhishek K. External capsular hyperintensities in Wilson’s disease presenting with refractory status epilepticus. Neurol India. Published online December 19, 2022.